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The 20th century commercial whaling industry severely reduced populations of great whales throughout the Southern Hemisphere. The effect of this exploitation on genetic diversity and population structure remains largely undescribed. Here, we compare pre- and post-whaling diversity of mitochondrial DNA (mtDNA) control region sequences for 3 great whales in the South Atlantic, such as the blue, humpback, and fin whale. Pre-whaling diversity is described from mtDNA extracted from bones collected near abandoned whaling stations, primarily from the South Atlantic island of South Georgia. These bones are known to represent the first stage of 20th century whaling and thus pre-whaling diversity of these populations. Post-whaling diversity is described from previously published studies reporting large-scale sampling of living whales in the Southern Hemisphere. Despite relatively high levels of surviving genetic diversity in the post-whaling populations, we found evidence of a probable loss of mtDNA lineages in all 3 species. This is evidenced by the detection of a large number of haplotypes found in the pre-whaling samples that are not present in the post-whaling samples. A rarefaction analysis further supports a loss of haplotypes in the South Atlantic humpback and Antarctic blue whale populations. The bones from former whaling stations in the South Atlantic represent a remarkable molecular archive for further investigation of the decline and ongoing recovery in the great whales of the Southern Hemisphere. [ABSTRACT FROM AUTHOR]

North Atlantic right whale (NARW) distribution shifts have led to increased presence in the US mid‐Atlantic, which includes the New York Bight (NYB), an area with substantial vessel traffic. NARW vessel strikes are mitigated by a seasonal management area (SMA) that is active November–April. Within the SMA, vessels ≥ 19.8 m must travel at ≤10 knots. However, until recently, surveys of the NYB were not conducted after the NARW distribution shifted. Thus, it was unclear whether the SMA captured NARW presence in the NYB. Outside the SMA, voluntary speed restrictions are implemented over a limited area when NARW calls are acoustically detected; therefore, it was important to quantify NARW vocal activity. Acoustic recordings (2016–2020) were analyzed to determine NARW presence, vocal states, and diel pattern of vocal activity. NARWs were detected outside SMA boundaries, and medium/high vocal states (21–69 calls over 3–6 h) occurred while the SMA was inactive. Therefore, the SMA spatiotemporal boundaries should be revised. Vocal activity was highest at night (22:00–1:00), and NARWs were acoustically detected when they were not detected by aerial surveys, illustrating acoustic detections are a viable method for triggering mitigation measures when NARWs are vocalizing but are not visually observed. [ABSTRACT FROM AUTHOR]

The New York Bight (NYB) is one of the busiest waterways along the US East Coast, and has recently seen an apparent increase in baleen whale presence. With growing anthropogenic pressures, a better understanding of their distribution and behaviour is needed. Encounter rates (sightings km−1) and behaviour of humpback (Megaptera novaeangliae), fin (Balaenoptera physalus) and minke (Balaenoptera acutorostrata) whales were obtained from dedicated non-systematic small vessel surveys conducted from May–November 2017–2019 in previously under-surveyed coastal areas of the NYB. Humpback whales were the most frequently sighted species, and their distribution in the NYB varied significantly by region and season. Within the mid-shelf region (10–60 km from shore), sightings of all species were generally concentrated spatially and temporally in mixed-species aggregations where feeding on sand lance (Ammodytes spp.) was observed. In the nearshore region (<10 km from shore), sightings of all species were more dispersed and typically occurred in close proximity to Atlantic menhaden (Brevoortia tyrannus). Humpback whales were commonly observed lunge feeding on these prey patches. The prevalence of foraging behaviour throughout the study area supports the hypothesis that the NYB may be an important supplementary feeding area for some species. Encounter rates were generally higher in areas overlapping with anthropogenic activity, suggesting that whales may be particularly vulnerable to anthropogenic impacts in the NYB. The observed species distribution patterns and importance of the NYB as a foraging habitat for baleen whales provides valuable information for the development of new baselines and best management practices within this heavily urbanized region. [ABSTRACT FROM AUTHOR]

Aim: Species distribution modelling is a useful tool for determining important habitats. By accounting for specific animal behaviour in the model, it is possible to identify finer‐scale patterns of habitat use. Together with spatially explicit data on anthropogenic activities, models can be used to assess human impacts and inform conservation management. This study used observations of breeding behaviour to identify fine‐scale breeding habitats of humpback whales (Megaptera novaeangliae), as well as potential overlap of these habitats with cumulative anthropogenic impacts. Location: Eastern Tropical Atlantic, West Africa. Methods: Maxent was used to model humpback distribution using pertinent environmental predictors and an integrated dataset of humpback whale occurrences filtered for breeding‐specific behaviours. In conjunction with multiple anthropogenic activities, a subsequent cumulative utilization and impact analysis assessed the degree of overlap between predicted breeding habitat and potential anthropogenic impacts. Results: Greatest habitat suitability occurred in warm coastal waters of Gabon, and other highly suitable areas occurred off Equatorial Guinea (Bioko Island), Cameroon and Angola. Sea surface temperature and height contributed most to the model. Highest overlap between humpback whales and potential impacts from anthropogenic activities occurred off Gabon, Equatorial Guinea (Bioko Island), Cameroon and Angola. Impacts associated with oil and gas development (where oil and gas platforms serve as an indicator for industry activity) appeared to contribute most to potential cumulative impact. Main Conclusions: Depth and sea surface temperature of predicted breeding habitats were consistent with previous studies. However, lesser known characteristics such as sea surface height and wind speed, resulting in potentially more sheltered areas for breeding whales, may also be important in delineating finer‐scale habitat suitability. Identified areas of high potential cumulative impact occurred within exclusive economic zones of multiple countries and likely represent the minimum level of impact to humpback whales in the region, highlighting the need for additional research and effective management throughout the area. [ABSTRACT FROM AUTHOR]

The article discusses the common nonsong social calls of humpback whales recorded off northern Angola, southern Africa. Topics include passive acoustic monitoring using remote autonomous recorders as a proven method for establishing information on the diversity and distribution of cetacean species, Humpback whales (Megaptera novaeangliae) as one of the most frequently sighted species off northern Angola, and lack of rhythmic and continuous pattern of song in social calls.